Print Email Facebook Twitter Full-scale increased iron dosage to stimulate the formation of vivianite and its recovery from digested sewage sludge Title Full-scale increased iron dosage to stimulate the formation of vivianite and its recovery from digested sewage sludge Author Prot, T.J.F. (TU Delft BT/Environmental Biotechnology; Wetsus, Centre for Sustainable Water Technology) Wijdeveld, W. (Wetsus, Centre for Sustainable Water Technology) Eshun, L. Ekua (Wetsus, Centre for Sustainable Water Technology) Dugulan, A.I. (TU Delft RID/TS/Instrumenten groep) Goubitz, K. (TU Delft RST/Technici Pool) Korving, L. (Wetsus, Centre for Sustainable Water Technology) van Loosdrecht, Mark C.M. (TU Delft BT/Environmental Biotechnology) Date 2020 Abstract The recovery of phosphorus from secondary sources like sewage sludge is essential in a world suffering from resources depletion. Recent studies have demonstrated that phosphorus can be magnetically recovered as vivianite (Fe(II)3(PO4)2∗8H2O) from the digested sludge (DS) of Waste Water Treatment Plants (WWTP) dosing iron. To study the production of vivianite in digested sludge, the quantity of Fe dosed at the WWTP of Nieuwveer (The Netherlands) was increased (from 0.83 to 1.53 kg Fe/kg P in the influent), and the possible benefits for the functioning of the WWTP were evaluated. Higher Fe dosing is not only relevant for P-recovery, but also for maximal recovery of organics from influent for e.g. biogas production. The share of phosphorus present as vivianite in the DS increased from 20% to 50% after the increase in Fe dosing, making more phosphorus available for future magnetic recovery. This increase was directly proportional to the increase of Fe in DS, suggesting that vivianite could be favored not only thermodynamically, but also kinetically. Interestingly, analyses suggest that several types of vivianite are formed in the WWTP, and could differ in their purity, oxidation state or crystallinity. These differences could have an impact on the subsequent magnetic separation. Following the Fe dosing increase, P in the effluent and H2S in the biogas both decreased: 1.28 to 0.42 ppm for P and 26 to 8 ppm for H2S. No negative impact on the nitrogen removal, biogas production, COD removal or dewaterability was observed. Since quantification of vivianite in DS is complicated, previous studies were reviewed and we proposed a more accurate Mössbauer spectroscopy analysis and fitting for sludge samples. This study is important from a P recovery point of view, but also because iron addition can play a crucial role in future resource recovery wastewater facilities. Subject Iron sulphideMagnetic recoveryMössbauer spectroscopyPhosphorus recoveryWaste water treatment plant (WWTP)X-ray diffraction (XRD) To reference this document use: http://resolver.tudelft.nl/uuid:3a03e464-0ce9-4530-9a2c-fa19036e2032 DOI https://doi.org/10.1016/j.watres.2020.115911 ISSN 0043-1354 Source Water Research, 182 Part of collection Institutional Repository Document type journal article Rights © 2020 T.J.F. Prot, W. Wijdeveld, L. Ekua Eshun, A.I. Dugulan, K. Goubitz, L. Korving, Mark C.M. van Loosdrecht Files PDF 1_s2.0_S0043135420304486_main.pdf 3.36 MB Close viewer /islandora/object/uuid%3A3a03e464-0ce9-4530-9a2c-fa19036e2032/datastream/OBJ/view